右冠動脈近位部病変に対してDCAを施行し，nose cone injuryと思われるprolonged spasmを来した1例

A Case of Prolonged Coronary Spasm with Nose Cone Injury during Directional Coronary Atherectomy of the Proximal Right Coronary Artery

　Directional coronary atherectomy（DCA）は，冠動脈狭窄の原因であるアテローマを直接取り除き，内腔をスムーズに，かつより大きくし，PTCAの弱点である急性冠閉塞，再狭窄の問題を解決する目的で開発された新しい治療法である．しかし，臨床に盛んに施行されるにつれて，DCA特有の合併症が報告されている．今回われわれは，DCA施行中，病変部より遠位部で急性冠閉塞を来し，同時に施行中であった血管内超音波法で，血栓と思われる像を認め，isosorbide dinitrate（ISDN），ウロキナーゼの冠動脈内投与およびrepeat　PTCA,intra-aortic balloon pumping（IABP）にてbail outした症例を経験したので報告する．

Directional coronary atherectomy (DCA) is a new technique of coronary revascularization by which ather-osclerotic plaque is excised and retrieved from the target lesion. A larger and smother lumen is obtainable compared with that seen after percutaneous trans-luminal coronary angioplasty (PTCA). Using this factor we may overcome a limitation found in acute coronary occlusion and restenosis after PTCA. How-ever, there are some unique complications associated with DCA, which are encountered rather frequently. We identified a case of abrupt vessel closure in an artery remote from the target vessel during prolonged coronary spasm. In this case there was nose cone injury during DCA of the proximal right coronary artery and thrombus like image was detected by intravascular ultrasound. Intracoronary isosorbide dinitrate and urokinase were administered and PTCA was performed with intra - aortic balloon pumping. After this proce-dure, revascularization of the right coronary artery was achieved with excellent results.